The filtering devices for thermoplastics which are in the molten state and, in particular, originate from recycled plastic waste are known. The plastic melt is in this case conducted via filter arrangements in order to filter out impurities. Filtering devices of this type possess a number of screening nests in which filter arrangements lie. These filter arrangements have to be backwashed from time to time and, if they are blocked, have to be exchanged, in order to achieve satisfactory filtration and a satisfactory passage of the plastic melt.